Engine cooling fan with ring reinforcement

ABSTRACT

A cooling fan for use in an engine of an automotive vehicle includes a central hub, a plurality of blades and an annular reinforcement element. The central hub is pivotally coupled to the vehicle. The plurality of blades has distal ends spaced radially outwardly relative to the central hub. The annular reinforcement element is fixedly secured to the plurality of blades, the reinforcement element is spaced radially inwardly relative to the distal ends of the plurality of blades to prevent a build-up of ice between the fan and a shroud or housing surrounding the fan.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a cooling fan of an engine for an automotive vehicle. More particularly, the invention relates to a cooling fan having an outer periphery and an annular reinforcement member spaced radially inwardly from the outer periphery.

2. Description of the Related Art

An automotive vehicle includes an internal combustion engine and a radiator for exhausting heat emitted by the engine. Specifically, liquid is forced through passages and cavities within a block of the engine via an engine-driven impeller. The liquid is heated by the block. Heat is carried away from the block as the liquid passes through the radiator. While the vehicle is moving, air is continuously funneled toward the radiator. Heat is exchanged with the air as it passes around and through the radiator. The heat exchange cools the liquid passing through the radiator. The liquid is returned to the passages and cavities of the block, where the liquid again takes on the heat of the engine. The cycle repeats as long as the engine remains running.

A belt or electrically driven fan is used for forcing air toward the radiator, particularly while the vehicle is stopped or moving too slow for effective heat exchange with the air. The fan typically includes a central hub pivotally coupled to the vehicle frame or engine block. A plurality of fins or blades extends radially outwardly from the central hub. A protective shroud is often used to protect the blades and to promote a more efficient flow of air through the fan and to the radiator.

Conventional fan designs typically include a reinforcement ring fixedly secured to the radially outermost tips of the blades. The reinforcement ring allows the use of thinner blades, thereby reducing rotational mass of the fan and the amount of material used to form the fan. The problem with the reinforcement ring in conventional fan designs is that in cold environments, ice can form between the reinforcement ring and the protective shroud. The ice can impede rotational movement of the fan, which can cause damage to the fan when the engine is started. The engine can also be damaged as heat energy accumulates in the engine and is not properly exhausted by the radiator.

Accordingly, it remains desirable to provide an inventive fan design that is lighter, cheaper and at least as strong as conventional fan designs.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a cooling fan is provided for use in an engine of an automotive vehicle. The fan includes a central hub, a plurality of blades and an annular reinforcement element. The central hub is pivotally coupled to the vehicle. The plurality of blades has distal ends spaced radially outwardly relative to the central hub. The annular reinforcement element is fixedly secured to the plurality of blades, the reinforcement element is spaced radially inwardly relative to the distal ends of the plurality of blades.

According to another aspect of the invention, an automotive vehicle includes a fan shroud and a cooling fan. The fan shroud has an outer wall defining a generally cylindrical space. The cooling fan is pivotally coupled to the vehicle. The fan is disposed within the cylindrical space of the fan shroud. The fan has a central hub, a plurality of blades and an annular reinforcement element. The central hub is pivotally coupled to the vehicle. The plurality of blades has distal ends spaced radially outwardly relative to the central hub. The annular reinforcement element is fixedly secured to the plurality of blades, the reinforcement element being spaced apart from the outer wall of the shroud so as to minimize a build-up of ice therebetween.

According to another aspect of the invention, the reinforcement element is integrally formed with the plurality of blades.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein:

FIG. 1 is a front elevational view of an automotive vehicle having a fan and a fan shroud according to one embodiment of the invention; and

FIG. 2 is a front elevational view of the fan according to a second embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, a front end of an automotive vehicle is shown having a radiator 10, a fan shroud 12 and a cooling fan 14. The radiator 10 is of conventional design for cooling liquid passing through a block of an engine by way of heat exchange with air directed toward the radiator 10 while the vehicle is moving and/or with air propelled toward the radiator 10 by rotation of the fan 14. The fan 14 is driven by an engine driven serpentine belt or by an electric motor powered by the vehicle electrical system.

The fan shroud 12 includes an outer wall 16 defining a generally cylindrical space. The fan 14 is pivotally coupled to the vehicle. The fan 14 is disposed within the cylindrical space.

The fan 14 includes a central hub 20. The hub 20 is generally cylindrical. The fan 14 includes a plurality of fins or blades 22 shaped for directing air toward the radiator during rotation of the fan 14 in a driven direction. The fan 14 has at least three blades 22. The blades 22 extend radially outwardly from the hub 20. Each of the blades 22 has a distal end 24.

In some conventional fan designs, a reinforcement element is fixedly secured to the distal ends of the blades for enhancing the rigidity of the fan. That is, the reinforcement element in a conventional fan defines an outermost periphery of the fan relative to the central hub. The reinforcement element is typically positioned in close proximity to the outer wall of the fan shroud. In cold conditions, ice can form between reinforcement element and the fan shroud. The ice can impede rotation of the fan when the engine is cold started. Impeding rotation of the fan can damage both the fan itself or the engine due to overheating as a result of degraded cooling performance.

The fan 14 according to an embodiment of the invention overcomes the problem of ice build-up by providing a reinforcement element 30 that is spaced radially inwardly from the distal ends 24 of the blades 22 and the outer wall 16 of the shroud 12. More specifically, the reinforcement element 30 has a generally continuous annular shape. Preferably, the reinforcement element 30 is integrally formed with the blades 22. Illustratively, the fan 14 is formed in an injection molding process from a plastic material selected from the group consisting of: glass reinforced nylon, ABS,______, ______, ______. Optionally, the reinforcement element 30′ is defined by a discontinuous series of webs 40 each of which extend between and interconnect adjacent blades 22′.

In one application of the invention, the blades 22 have a predetermined length ranging between ______ and ______. The reinforcement element 30 is spaced radially inwardly from the distal ends 24 by a distance ranging between 10-50% of the predetermined length. In another application of the invention, the reinforcement element is spaced radially inwardly from the outer wall of the shroud by a distance ranging between 12-60% of the predetermined length of the blades 22.

The invention has been described in an illustrative manner. It is, therefore, to be understood that the terminology used is intended to be in the nature of words of description rather than of limitation. Many modifications and variations of the invention are possible in light of the above teachings. Thus, within the scope of the appended claims, the invention may be practiced other than as specifically described. 

1. A cooling fan for use in an engine of an automotive vehicle, said fan comprising: a central hub pivotally coupled to the vehicle; a plurality of blades, each of said plurality of blades having a distal end spaced radially outwardly relative to said central hub; and an annular reinforcement element fixedly secured to said plurality of blades, said reinforcement element being spaced radially inwardly relative to said distal ends of said plurality of blades.
 2. The cooling fan as set forth in claim 1, wherein said reinforcement element is integrally formed with said plurality of blades.
 3. The cooling fan as set forth in claim 1, wherein said plurality of blades have a predetermined length, said reinforcement element being spaced radially inwardly from said distal ends by a distance ranging between 10-50% of said predetermined length.
 4. The cooling fan as set forth in claim 1, wherein said reinforcement element is a substantially continuous ring.
 5. The cooling fan as set forth in claim 1 having at least three blades extending radially outwardly from said central hub.
 6. A cooling assembly for a radiator for an automotive vehicle, said cooling assembly comprising: a fan shroud having an outer wall defining a generally cylindrical space; a cooling fan pivotally coupled to said vehicle, said fan disposed within said cylindrical space of said fan shroud, said fan having a central hub pivotally coupled to the vehicle; a plurality of blades having distal ends spaced radially outwardly relative to said central hub; and an annular reinforcement element fixedly secured to said plurality of blades, said reinforcement element being spaced apart from said outer wall of said shroud so as to minimize a build-up of ice therebetween.
 7. The cooling fan as set forth in claim 6, wherein said reinforcement element is integrally formed from plastic with said plurality of blades.
 8. The cooling fan as set forth in claim 6, wherein said plurality of blades have a predetermined length, said reinforcement element being spaced radially inwardly from said outer wall of said shroud by a distance ranging between 12-60% of said predetermined length. 